`Assertion failed: Too many unresolved delimiter token lengths` for enum cases with associated values when using `prioritizeKeepingFunctionOutputTogether: true`

[ahoppen]

Formatting the following file with the following configuration cause an assertion failure

enum Error {
  case alreadyOpen(Int)
}

{
    "version": 1,
    "prioritizeKeepingFunctionOutputTogether": true
}

Stack trace:

Thread 0 Crashed::  Dispatch queue: com.apple.main-thread
0   libswiftCore.dylib            	       0x1947691e8 _assertionFailure(_:_:file:line:flags:) + 268
1   swift-format                  	       0x10316b5c8 PrettyPrinter.prettyPrint() + 4568 (PrettyPrint.swift:680)
2   swift-format                  	       0x10317c380 SwiftFormatter.format<A>(syntax:operatorTable:assumingFileURL:source:to:) + 1376 (SwiftFormatter.swift:164)
3   swift-format                  	       0x10317bd20 SwiftFormatter.format<A>(source:assumingFileURL:to:parsingDiagnosticHandler:) + 428 (SwiftFormatter.swift:110)
4   swift-format                  	       0x103bc3fd4 FormatFrontend.processFile(_:) + 1560 (FormatFrontend.swift:65)
5   swift-format                  	       0x103bc69bc implicit closure #8 in implicit closure #7 in Frontend.processURLs(_:parallel:) + 56 (Frontend.swift:143)
6   swift-format                  	       0x103bc69e8 thunk for @callee_guaranteed (@guaranteed Frontend.FileToProcess) -> (@error @owned Error) + 28
7   swift-format                  	       0x103bc887c partial apply for thunk for @callee_guaranteed (@guaranteed Frontend.FileToProcess) -> (@error @owned Error) + 28
8   libswiftCore.dylib            	       0x19480a9f8 Sequence.forEach(_:) + 688
9   swift-format                  	       0x103bc66ec Frontend.processURLs(_:parallel:) + 1356 (Frontend.swift:143)
10  swift-format                  	       0x103bc5da0 Frontend.run() + 516 (Frontend.swift:93)
11  swift-format                  	       0x103bbf6fc closure #1 in SwiftFormatCommand.Format.run() + 116 (Format.swift:45)
12  swift-format                  	       0x103bbf7f8 partial apply for closure #1 in SwiftFormatCommand.Format.run() + 24
13  swift-format                  	       0x103bd5e90 PerformanceMeasurementsOptions.printingInstructionCountIfRequested<A>(_:) + 140 (PerformanceMeasurement.swift:24)
14  swift-format                  	       0x103bbf608 SwiftFormatCommand.Format.run() + 160 (Format.swift:43)
15  swift-format                  	       0x103bc0e74 protocol witness for ParsableCommand.run() in conformance SwiftFormatCommand.Format + 44
16  swift-format                  	       0x102fc6910 static ParsableCommand.main(_:) + 576 (ParsableCommand.swift:142)
17  swift-format                  	       0x102fc715c static ParsableCommand.main() + 52 (ParsableCommand.swift:159)
18  swift-format                  	       0x103bda73c static SwiftFormatCommand.$main() + 40
19  swift-format                  	       0x103bdb524 main + 12 (SwiftFormatCommand.swift:18)
20  dyld                          	       0x184b010e0 start + 2360

[ahoppen]

Synced to Apple’s issue tracker as rdar://126994097